import random
res=[]
str=''
k=0
num=['0','1','2','3','4','5','6','7','8','9']
up=['A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']
low=['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']
while k<200:
    str=''
    for i in range(10):
        i= random.randint(1,3)
        if i ==1:
            j=random.randint(0,9)
            str+=num[j]
        elif i==2:
            j=random.randint(0,25)
            str+=up[j]
        else:
            j=random.randint(0,25)
            str+=low[j]
    if str not in res:
        res.append(str)
        k+=1
        print(str)
        

